1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * c 2001 PPC 64 Team, IBM Corp
4 */
5
6 #include <linux/smp.h>
7 #include <linux/export.h>
8 #include <linux/memblock.h>
9 #include <linux/sched/task.h>
10 #include <linux/numa.h>
11 #include <linux/pgtable.h>
12
13 #include <asm/lppaca.h>
14 #include <asm/paca.h>
15 #include <asm/sections.h>
16 #include <asm/kexec.h>
17 #include <asm/svm.h>
18 #include <asm/ultravisor.h>
19
20 #include "setup.h"
21
22 #ifndef CONFIG_SMP
23 #define boot_cpuid 0
24 #endif
25
alloc_paca_data(unsigned long size,unsigned long align,unsigned long limit,int cpu)26 static void *__init alloc_paca_data(unsigned long size, unsigned long align,
27 unsigned long limit, int cpu)
28 {
29 void *ptr;
30 int nid;
31
32 /*
33 * boot_cpuid paca is allocated very early before cpu_to_node is up.
34 * Set bottom-up mode, because the boot CPU should be on node-0,
35 * which will put its paca in the right place.
36 */
37 if (cpu == boot_cpuid) {
38 nid = NUMA_NO_NODE;
39 memblock_set_bottom_up(true);
40 } else {
41 nid = early_cpu_to_node(cpu);
42 }
43
44 ptr = memblock_alloc_try_nid(size, align, MEMBLOCK_LOW_LIMIT,
45 limit, nid);
46 if (!ptr)
47 panic("cannot allocate paca data");
48
49 if (cpu == boot_cpuid)
50 memblock_set_bottom_up(false);
51
52 return ptr;
53 }
54
55 #ifdef CONFIG_PPC_PSERIES
56
57 #define LPPACA_SIZE 0x400
58
alloc_shared_lppaca(unsigned long size,unsigned long limit,int cpu)59 static void *__init alloc_shared_lppaca(unsigned long size, unsigned long limit,
60 int cpu)
61 {
62 size_t shared_lppaca_total_size = PAGE_ALIGN(nr_cpu_ids * LPPACA_SIZE);
63 static unsigned long shared_lppaca_size;
64 static void *shared_lppaca;
65 void *ptr;
66
67 if (!shared_lppaca) {
68 memblock_set_bottom_up(true);
69
70 /*
71 * See Documentation/powerpc/ultravisor.rst for more details.
72 *
73 * UV/HV data sharing is in PAGE_SIZE granularity. In order to
74 * minimize the number of pages shared, align the allocation to
75 * PAGE_SIZE.
76 */
77 shared_lppaca =
78 memblock_alloc_try_nid(shared_lppaca_total_size,
79 PAGE_SIZE, MEMBLOCK_LOW_LIMIT,
80 limit, NUMA_NO_NODE);
81 if (!shared_lppaca)
82 panic("cannot allocate shared data");
83
84 memblock_set_bottom_up(false);
85 uv_share_page(PHYS_PFN(__pa(shared_lppaca)),
86 shared_lppaca_total_size >> PAGE_SHIFT);
87 }
88
89 ptr = shared_lppaca + shared_lppaca_size;
90 shared_lppaca_size += size;
91
92 /*
93 * This is very early in boot, so no harm done if the kernel crashes at
94 * this point.
95 */
96 BUG_ON(shared_lppaca_size > shared_lppaca_total_size);
97
98 return ptr;
99 }
100
101 /*
102 * See asm/lppaca.h for more detail.
103 *
104 * lppaca structures must must be 1kB in size, L1 cache line aligned,
105 * and not cross 4kB boundary. A 1kB size and 1kB alignment will satisfy
106 * these requirements.
107 */
init_lppaca(struct lppaca * lppaca)108 static inline void init_lppaca(struct lppaca *lppaca)
109 {
110 BUILD_BUG_ON(sizeof(struct lppaca) != 640);
111
112 *lppaca = (struct lppaca) {
113 .desc = cpu_to_be32(0xd397d781), /* "LpPa" */
114 .size = cpu_to_be16(LPPACA_SIZE),
115 .fpregs_in_use = 1,
116 .slb_count = cpu_to_be16(64),
117 .vmxregs_in_use = 0,
118 .page_ins = 0, };
119 };
120
new_lppaca(int cpu,unsigned long limit)121 static struct lppaca * __init new_lppaca(int cpu, unsigned long limit)
122 {
123 struct lppaca *lp;
124
125 BUILD_BUG_ON(sizeof(struct lppaca) > LPPACA_SIZE);
126
127 if (early_cpu_has_feature(CPU_FTR_HVMODE))
128 return NULL;
129
130 if (is_secure_guest())
131 lp = alloc_shared_lppaca(LPPACA_SIZE, limit, cpu);
132 else
133 lp = alloc_paca_data(LPPACA_SIZE, 0x400, limit, cpu);
134
135 init_lppaca(lp);
136
137 return lp;
138 }
139 #endif /* CONFIG_PPC_PSERIES */
140
141 #ifdef CONFIG_PPC_64S_HASH_MMU
142 /*
143 * 3 persistent SLBs are allocated here. The buffer will be zero
144 * initially, hence will all be invaild until we actually write them.
145 *
146 * If you make the number of persistent SLB entries dynamic, please also
147 * update PR KVM to flush and restore them accordingly.
148 */
new_slb_shadow(int cpu,unsigned long limit)149 static struct slb_shadow * __init new_slb_shadow(int cpu, unsigned long limit)
150 {
151 struct slb_shadow *s;
152
153 if (cpu != boot_cpuid) {
154 /*
155 * Boot CPU comes here before early_radix_enabled
156 * is parsed (e.g., for disable_radix). So allocate
157 * always and this will be fixed up in free_unused_pacas.
158 */
159 if (early_radix_enabled())
160 return NULL;
161 }
162
163 s = alloc_paca_data(sizeof(*s), L1_CACHE_BYTES, limit, cpu);
164
165 s->persistent = cpu_to_be32(SLB_NUM_BOLTED);
166 s->buffer_length = cpu_to_be32(sizeof(*s));
167
168 return s;
169 }
170 #endif /* CONFIG_PPC_64S_HASH_MMU */
171
172 /* The Paca is an array with one entry per processor. Each contains an
173 * lppaca, which contains the information shared between the
174 * hypervisor and Linux.
175 * On systems with hardware multi-threading, there are two threads
176 * per processor. The Paca array must contain an entry for each thread.
177 * The VPD Areas will give a max logical processors = 2 * max physical
178 * processors. The processor VPD array needs one entry per physical
179 * processor (not thread).
180 */
181 struct paca_struct **paca_ptrs __read_mostly;
182 EXPORT_SYMBOL(paca_ptrs);
183
initialise_paca(struct paca_struct * new_paca,int cpu)184 void __init initialise_paca(struct paca_struct *new_paca, int cpu)
185 {
186 #ifdef CONFIG_PPC_PSERIES
187 new_paca->lppaca_ptr = NULL;
188 #endif
189 #ifdef CONFIG_PPC_BOOK3E_64
190 new_paca->kernel_pgd = swapper_pg_dir;
191 #endif
192 new_paca->lock_token = 0x8000;
193 new_paca->paca_index = cpu;
194 new_paca->kernel_toc = kernel_toc_addr();
195 new_paca->kernelbase = (unsigned long) _stext;
196 /* Only set MSR:IR/DR when MMU is initialized */
197 new_paca->kernel_msr = MSR_KERNEL & ~(MSR_IR | MSR_DR);
198 new_paca->hw_cpu_id = 0xffff;
199 new_paca->kexec_state = KEXEC_STATE_NONE;
200 new_paca->__current = &init_task;
201 new_paca->data_offset = 0xfeeeeeeeeeeeeeeeULL;
202 #ifdef CONFIG_PPC_64S_HASH_MMU
203 new_paca->slb_shadow_ptr = NULL;
204 #endif
205
206 #ifdef CONFIG_PPC_BOOK3E_64
207 /* For now -- if we have threads this will be adjusted later */
208 new_paca->tcd_ptr = &new_paca->tcd;
209 #endif
210 }
211
212 /* Put the paca pointer into r13 and SPRG_PACA */
setup_paca(struct paca_struct * new_paca)213 void setup_paca(struct paca_struct *new_paca)
214 {
215 /* Setup r13 */
216 local_paca = new_paca;
217
218 #ifdef CONFIG_PPC_BOOK3E_64
219 /* On Book3E, initialize the TLB miss exception frames */
220 mtspr(SPRN_SPRG_TLB_EXFRAME, local_paca->extlb);
221 #else
222 /*
223 * In HV mode, we setup both HPACA and PACA to avoid problems
224 * if we do a GET_PACA() before the feature fixups have been
225 * applied.
226 *
227 * Normally you should test against CPU_FTR_HVMODE, but CPU features
228 * are not yet set up when we first reach here.
229 */
230 if (mfmsr() & MSR_HV)
231 mtspr(SPRN_SPRG_HPACA, local_paca);
232 #endif
233 mtspr(SPRN_SPRG_PACA, local_paca);
234
235 }
236
237 static int __initdata paca_nr_cpu_ids;
238 static int __initdata paca_ptrs_size;
239 static int __initdata paca_struct_size;
240
allocate_paca_ptrs(void)241 void __init allocate_paca_ptrs(void)
242 {
243 paca_nr_cpu_ids = nr_cpu_ids;
244
245 paca_ptrs_size = sizeof(struct paca_struct *) * nr_cpu_ids;
246 paca_ptrs = memblock_alloc_raw(paca_ptrs_size, SMP_CACHE_BYTES);
247 if (!paca_ptrs)
248 panic("Failed to allocate %d bytes for paca pointers\n",
249 paca_ptrs_size);
250
251 memset(paca_ptrs, 0x88, paca_ptrs_size);
252 }
253
allocate_paca(int cpu)254 void __init allocate_paca(int cpu)
255 {
256 u64 limit;
257 struct paca_struct *paca;
258
259 BUG_ON(cpu >= paca_nr_cpu_ids);
260
261 #ifdef CONFIG_PPC_BOOK3S_64
262 /*
263 * We access pacas in real mode, and cannot take SLB faults
264 * on them when in virtual mode, so allocate them accordingly.
265 */
266 limit = min(ppc64_bolted_size(), ppc64_rma_size);
267 #else
268 limit = ppc64_rma_size;
269 #endif
270
271 paca = alloc_paca_data(sizeof(struct paca_struct), L1_CACHE_BYTES,
272 limit, cpu);
273 paca_ptrs[cpu] = paca;
274
275 initialise_paca(paca, cpu);
276 #ifdef CONFIG_PPC_PSERIES
277 paca->lppaca_ptr = new_lppaca(cpu, limit);
278 #endif
279 #ifdef CONFIG_PPC_64S_HASH_MMU
280 paca->slb_shadow_ptr = new_slb_shadow(cpu, limit);
281 #endif
282 paca_struct_size += sizeof(struct paca_struct);
283 }
284
free_unused_pacas(void)285 void __init free_unused_pacas(void)
286 {
287 int new_ptrs_size;
288
289 new_ptrs_size = sizeof(struct paca_struct *) * nr_cpu_ids;
290 if (new_ptrs_size < paca_ptrs_size)
291 memblock_phys_free(__pa(paca_ptrs) + new_ptrs_size,
292 paca_ptrs_size - new_ptrs_size);
293
294 paca_nr_cpu_ids = nr_cpu_ids;
295 paca_ptrs_size = new_ptrs_size;
296
297 #ifdef CONFIG_PPC_64S_HASH_MMU
298 if (early_radix_enabled()) {
299 /* Ugly fixup, see new_slb_shadow() */
300 memblock_phys_free(__pa(paca_ptrs[boot_cpuid]->slb_shadow_ptr),
301 sizeof(struct slb_shadow));
302 paca_ptrs[boot_cpuid]->slb_shadow_ptr = NULL;
303 }
304 #endif
305
306 printk(KERN_DEBUG "Allocated %u bytes for %u pacas\n",
307 paca_ptrs_size + paca_struct_size, nr_cpu_ids);
308 }
309
310 #ifdef CONFIG_PPC_64S_HASH_MMU
copy_mm_to_paca(struct mm_struct * mm)311 void copy_mm_to_paca(struct mm_struct *mm)
312 {
313 mm_context_t *context = &mm->context;
314
315 VM_BUG_ON(!mm_ctx_slb_addr_limit(context));
316 memcpy(&get_paca()->mm_ctx_low_slices_psize, mm_ctx_low_slices(context),
317 LOW_SLICE_ARRAY_SZ);
318 memcpy(&get_paca()->mm_ctx_high_slices_psize, mm_ctx_high_slices(context),
319 TASK_SLICE_ARRAY_SZ(context));
320 }
321 #endif /* CONFIG_PPC_64S_HASH_MMU */
322